docs: def TriCross(self, A=[(100, 0, 0), (0, 50, 60)], B=[(50, 50, 0), (0, 0, 100)]):
  
          '''
          Return the crosspoint of two line A and B in triangular coord.
          :param A: first line
          :type A: a list consist of two tuples, beginning and end point of the line
          :param B: second line
          :type B: a list consist of two tuples, beginning and end point of the line
          :return:  the crosspoint of A and B
          :rtype:   a list consist of three numbers, the x-y-z of the triangular coord
          '''
  
          x0, y0 = self.TriToBin(A[0][0], A[0][1], A[0][2])
          x1, y1 = self.TriToBin(A[1][0], A[1][1], A[1][2])
          x2, y2 = self.TriToBin(B[0][0], B[0][1], B[0][2])
          x3, y3 = self.TriToBin(B[1][0], B[1][1], B[1][2])
  
          b1 = (y1 - y0) / (x1 - x0)
          b2 = (y3 - y2) / (x3 - x2)
          c1 = y0 - b1 * x0
          c2 = y2 - b2 * x2
  
          x = (c2 - c1) / (b1 - b2)
          y = b1 * x + c1
  
          result = self.BinToTri(x, y)
          return (result)